At Some Disputed Barricade

Fans of the first three books in this WWI series from Perry, best known for her Victorian police procedurals, will eagerly pick up this fourth volume to learn more of the ongoing saga of the three Reavley siblings: Joseph, a chaplain working with soldiers on the front line in France; Matthew, a British intelligence officer; and Judith, an ambulance driver. (Newcomers may struggle to understand the backstory.) Matthew continues his search for the traitorous mastermind—the "Peacemaker"—plotting to align Britain with Germany to end the war, while Joseph is working on a smaller mystery: was British officer Howard Northrop killed by one of his own men? Exposition slows down the pace in places, but the author vividly captures the unspeakable horrors of the Great War. Readers won't have long to wait for the fifth and final entry in the series, We Shall Not Sleep (Reviews, Feb. 5). (Mar.)